Si-Based GeSn Photodetector for Mid-Infrared Integrated Microwave Photonics

A high-speed Si-based Germanium-Tin (GeSn) photodetector is designed and simulated for infrared integrated microwave photonic applications. The design is based on the CVD-grown GeSn bulk NIP photodetector structure with 8% Sn composition optimized for the detection wavelength up to 2 um that can be extended to mid and far infrared spectra with higher Sn compositions. The electrical direct current (DC) and frequency response simulation results showed the responsivity of 0.02 A/W and maximum -3 dB bandwidth of 10 GHz at 2 μm. This work indicates the GeSn high-speed photodetector as a promising candidate for future of infrared microwave communication.